This invention relates generally to structure and system health monitoring and more particularly, to methods and systems for monitoring structure and system health using networked smart wireless sensor devices.
At least some known applications for wireless communication networks include industrial control and monitoring, intelligent agriculture, asset and inventory tracking, and security. Typical wireless sensing systems comprise wireless sensors that passively gather large amounts of data from an environment, which is typically transmitted to a host node for evaluation by an individual specifically trained to manually evaluate the information as time permits. This typical sensor system sometimes includes conversion of the signal from analog to digital and/or signal conditioning. The raw time-series data is typically transmitted in its entirety to a host node where it is sometimes stored indefinitely and analyzed very infrequently.
A conventional system comprises a plurality of sensors coupled to an interface which sends the information via a wired, large bandwidth transmission to a computer at a remote location. Installation of the wires themselves are cost-prohibitive due to the distances over which the wires must pass, weight prohibitive due to the amount of the wiring, or infeasible in many other situations due to the environment where the sensor itself and respective wiring are located. Low-power wireless technology has proved to be an enabler for wireless sensing in areas that were previously unattainable, due to the ‘difficult-to-reach’ or ‘difficult-to-wire’ nature of the installation or retrofit process. However, transmitting the raw data via a large bandwidth wireless system may consume significant amounts of power and create unnecessary network traffic.
Preprocessing is sometimes used to reduce the amount of network traffic using compression technology or by intelligently sending only the most pertinent data. However, reducing the data available for analysis also reduces the effectiveness of the analysis.